A little background... my parents are very generous and are paying for nearly my entire wedding. They are pretty well-off and helped pay for both of my brothers' weddings as well. My FI's family isn't paying for anything, as they can't really afford to help, which is fine with us. I didn't expect or ask for any money.
However, FI's father is very, very demanding with the guest list. Both FI and I didn't want any children at the wedding or reception, but he harassed us about it constantly - even having one of the kid's moms send us an email saying how upset she was - so we eventually caved in and allowed him to add a few children to the guest list.
Then he added some obscure cousins to the list (just one couple). Fine, we agreed and added them. Then, suddenly he remembered that they have a son our age who lives in the area, and wanted to add him. I even agreed to this. I called FI's father to ask for his name/address (because my FI didn't even know this guy's name!) and FI's father started giving me the names two other siblings my FI didn't know existed. And one is married. Obviously my FI didn't attend that wedding as he does not even know these people. I hate pulling the "money" card, but I feel like it is unreasonable for him to demand the addition of these guests, now 8 if we allow them all guests, when he is not paying. At $160/person (crazy, I know), I feel like asking my parents to pay for people we don't know and don't want at our wedding is a little unfair. Plus, we were given a budget and we are already on the top end. Is it rude to say this? I'm not sure how to politely say NO to these extra guests. Or say, just the parents, not the kids. We want our wedding to be small and intimate (we're hoping about 80 tops!) but now it's growing with people we don't even know.